feedback5 O21: 自选 kits for 麦哲伦, 令 and 电弧 (with their summons) and the 召唤师 summon deck

- kits/ops/op-mgllan.js, op-ling.js, op-radian.js: every skill, both talents, the trait and every module at every form,
  and the kits of their summons (龙腾.F / .L / .A, “清平” / “逍遥” / “弦惊”, 戴乌 / 赛柯 / 桑特拉).
- kits/shared/summoner.js (new): the summon deck the three share — the holding (charge_token[born], SUM-Y's +3), the
  return of a placed piece that left the field (owner on the field, redeploy time, one held, DP), recalls, the summons
  leaving with their owner (die_to_kill_token).
- kits/index.js: OPERATOR_KIT_FILES += op-mgllan.js, op-ling.js, op-radian.js; kits/README.md: the layout row and a
  pointer for summoner kits.
- tests: test/content/op_mgllan.test.js, op_ling.test.js, op_radian.test.js.
- golden: only diy moved — diy-106 … diy-109 now field the new kits' configurations (operator configurations are appended
  in OPERATOR_KIT_FILES order, so the prototype chunks shift back) and diy-110 … diy-115 are new; every other family is
  byte-identical.

server/sim/content/kits/README.md

@@ -15,6 +15,7 @@ operators, the self-select 6★ operators, contributions from GitHub issue #136
 | `ops/op-<codename>.js` | one 自选 operator kit per file (below: "How to add an operator (自选)") |
 | `shared/tier1.js` | the general kit helpers (blackboard readers, unit predicates, hit hooks, area queries, buffs, zones, free tiles, skill records) and the notes of the tier-1 kits |
 | `shared/tier2.js` … `tier6.js` | helpers two or more kits of that tier use, and that tier's notes (conventions, simplifications, fx kinds) |
+| `shared/summoner.js` | the 召唤师 summon deck the 自选 kits of 麦哲伦 / 令 / 电弧 share (`summonDeck`: the holding, a placed piece's return, recalls, the summons leaving with their owner; `holdBuff`, `tokenStat`) |
 | `tier1.js` … `tier6.js` | re-export shims for the old import paths; removed after the 0.2.0 refactor |
 
 `content/index.js` takes `KITS` from `index.js`: a unit's kit is `KITS[def.baseId]` (also the exact or the suffix-less
@@ -191,7 +192,9 @@ so a kit finds its pieces before the battle starts as `battle.allyUnits` with `k
 `ownerUnit === unit`, still undeployed (e.g. `op-bgsnow.js` gives its 打字机 pieces their kit in a talent's `install`
 with `battle._setupUnit(t, kit)`; `op-cgbird.js` counts its 幻影). A kit test fields a piece the same way:
 `units: [op, { uid, kind: 'token', tokenId, ownerUid, row, col }]` (`test/content/op_bgsnow.test.js`); the match side is
-covered by `test/match/diy-shop.test.js` (a DIY 鸿雪's 打字机 from prep to battle). Potential is 0 [ASSUMED: no account]. A new kit makes the operator a legal pick at once:
+covered by `test/match/diy-shop.test.js` (a DIY 鸿雪's 打字机 from prep to battle). A 召唤师 whose talent holds a deck of
+summons ("可以使用5个召唤物（最多同时部署3个）") takes `shared/summoner.js summonDeck` — the holding, a placed piece's return
+on its tile, recalls, its pieces' kits (`op-mgllan.js`, `op-ling.js`, `op-radian.js`). Potential is 0 [ASSUMED: no account]. A new kit makes the operator a legal pick at once:
 the server's `welcome.diyKitted` lists `KITTED_CHARS`, so the 自选编队 picker offers it and `room.diy` keeps it.
 
 **The fidelity rule and the checklist** above apply item by item: every skill at rank 4 and 7, every talent, every